Method of and apparatus for freezing fish



Dec. 15, 1931. A. c. WALWORTH METHOD OF AND APPARATUS FOR FREEZING FISHFiled April 16, 1929 3 Sheets-Sheet \w %m QM am Dec. 15, 1931. A. c.WALWORT METHOD OF AND APPARATUS FOR FREEZING FISH 3 Sheets-Sheet 2 FiledApril 6. 9 29 Jnvenlof:

23y Mam, (was 731 flilforlze ys Dec. 15, 1931. A. C YWALWORTH METHOD OFAND APPARATUS FOR FREEZING FISH Filed April 6. 1929 3 Sheets-Sheet 3 I lI G. M. 13,, 6mm

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Patented Dec. 15, 1931 PATENT OFFICE mnon c. wanwon'rn, or nnw'ron,mssaonusm'rs METHQDQI AND APPARATUS FOR rnnmme msn Application filedApril 16,

v This invention relates to the preservation of perishable goods byfreezing and particularly to the freezing of fish and similarfoodstuffs. It is common practice to lace fish in ice to preserve thesame for s ort periods of time. In cases where it has been desired topreserve the fish for longer periods of time, it has been common toplace the fish in containers setting in a cold brine or the like, thebrine bein cooled by a refrigerant conduit passing t rough the same. Thefreeiing'of fish in this manner often has resulted in injury to thecellular structure or tissues of the fish rendering it objectionable forcertain uses.

The present invention is based upon the discovery that fish may bepreserved by freezing without substantial injur to the in cellularstructure if the fish is sub ected 'to cooling under conditions'resulting'in rapidly freezing the fish. When fish are placed in'acontainer settin in a cool brine, freezing talgs place slow y becausethe heat is transferredbetween the fish andrefrigerant conduit byconvection. In accordance with the invention a rapid freezing of thefish is brought about by placing the fish in direct heatconducting'relation with the refrigerant in the conduit. It is theprimary object of the inventionwto provide a practical-andefiicient'method and apparatus whereby this can be effectively accomplished.

- It is a further object of the invention to provide means whereby thefish may be readily removed from the receptacle in which freezing takesplace..

Before explaining in detail the present invention, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanymg. drawings, since the invention'is capable of otherembodiments and of being practiced or carried out in various ways. Alsoit is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation, and itis not intended to limit'the invention beyond the terms of the severalclaims hereto ap- 1929. Serial a... 355,648.

pended as considered in view ofthelprior Fig. 3 is asectional detailview of one g freezing unit; 1

Figs. 4 and 5 are sectional detail views showing the relation betweenthe screws and nuts thereon and the cross members for supporting thetroughs;

Fig. 6 is a plan view of the end portion of a freezing apparatusembodying the invention; an

Fig. 7 is a fragmentary elevational view of the same. In theaccompanying drawings a plurality of sets of freezing unitsisillustrated each comprising a frame having side members 10 7 andincluding a series of pairs of spaced channels 11. The channel members11 of each ,pair are spaced apart and connected by blocks 12 each havingan unthreaded openlng 13 to receive a screw .14 positioned therebetween.Longitudinal movement of the screws 14 is prevented by flanges 15thereon engaglng one or more of the blocks 12. The series of pairs ofchannels 11 are connected by spaced longitudinal frame members 20, thespace therebetween being closed by doors 21 mounted on hinges 22 securedto. the longitudinal members 20. The side members .10 of the frame maybe connected at their ends by cross members 24.

.A plurality of superposed freezing units are movably mounted within theframe. For

'this purpose a plurality of nuts 33 are positioned similarly in spacedrelation on oppositely disposed screws 14. Gross members 31 extendbetween and rest upon similarly positioned nuts 33 and are provided atopposite ends with openings 32 to receive the screws 14, the arrangementbeing such as to provide a plurality of cross members 31 spaced apartYao outer ends provided with flanges 37 located in a common plane andforming a substantially continuous heat conducting surface connected ina heat conducting relation with the refrigerant conduits 35. The flanges37 at' the bottom of the fins 36, preferably, engage the bottom of thetroughs 30. A plurality of receptacles 38 composed of metal orequivalent heat conducting material are rovided for receiving the fishor similar oodstuffs to be frozen and are adapted to rest upon thesurface formed by the flanges 37. A pipe line 39 is connected at itsopposite ends to opposite ends of each of troughs and includes a pump(not shown) for circulatingbrinethrough the troughs as shown by thearrows in Fig. 1 in a direction opposite to the travel of thereceptacles38 therein.

Arms 40 are secured to the sides of each trough 30 in longitudinallyspaced relation and support longitudinally extending tracks 85 withsprockets 46. A continuous conveyor 50 is guided above and below thetrough-by the tracks 41 and 42 respectively and 1s guided around theends of the troughs by sprockets 46. A motor- 47 is mounted uponabracket at 4 one end of each trough 30 and is connected by a belt 48with a drivin sprocket 49 con-- nected with one of the sproc ets 46; Theconveyor 50 is provided withaplural ity of plates 51 adapted to engage areceptacle 38 and move the'same along the heat "cohducting surfaceformed by the flanges 37. Ifdesired the lates 51 of each convey lj maybe provided at'their'ends with brushes 52 adapted to engage thebottom ofthe trough to maintain the bottom free from ice or snow accumulations IThus, by positioning the adjacent troughs 30 together as closely aspossible the cooling medium of each assists the cooling action of theother.

Q In order to raise or lower one or more of 6 5 A pin 58 isadaptedtobe-inserted in the open- 41 spaced above the top of the trough and'ing 54 to engage one of the depressions 55 to lock the cross member'31to the nut 33 or to be inserted in the openings 56 to engage one of thedepressions 57 to lock the nuts 33 to the screws 14.

In the operation of the apparatus acooling fluid, such as a brine, ispassed into each trough 30 to a level slightly above the flanges \37 asshown at a in Figs. 1,2 and 3, and,' preferably, is circulated through'each trough 30 in a direction opposite to the travel of the receptaclesupon the flanges37. Thus, the

brine encloses the points of contact between that the fish are frozen bythe time the receptacles reach the extreme right hand pos i,

tion as shown in Fig. 1 and the receptacles are then removed. If it isdesired to raise or lower one of the units with respect to its adjacentunit the pins 58 are insertcd in the openin s54 so as to engage thecooperating depressions 55 in the nuts 33 supporting one of .the unitsand the pins 58 are inserted in the openings 56 inthe nuts 33 supportingthe adacent unit so as to engage the cooperating depressions 57 in thescrews. The screws 14 are then turned by means of the cranks 53whereupon the nuts 33 supporting the first 'unit' will be moved relativeto the screw and raise or lower the first unit while the nuts 33supporting the adjacent units will merely turn with the screw and willnot move relative thereto so that the units supported thereto simplifythe illustration, but it will be understood that where the size of thefreezing room limits the length of the freezing in'its,

the units are placed in parallel relation and the fish containingreceptacles are transferred from one unit and passed through theadjacent unit in an opposite direction. Each unit of the last set isprovided with means for facilitating the removal of the frozen fish fromthe ireceptacles. Thus, as illustrated diagrammatically in Figs. 6 and 7a platform 60 may be supported upon the rear end of each trough 30 ofall sets except the t P1". In an apparatus for freezing fish and last asby brackets 61 and a platform 62 may be supported upon the front end ofeach trough as by brackets 63, It will be understood that, each freezingunit extends substantially the length of the freezing room and that thereceptacles 38 may be transferred either manually or by suitableconveyors from one unit to theadjacent units and 1 passed throughadjacent units in opposite directions. I I

At the rear end of the final set of freezing units means are providedforfacilitating the removal of the fish from the receptacles, but it willbeunderstood that similar expedients may be employed where a single setof freezing units are used. As shown in Figs. 6 and 7 a supplementalframe is'provided adjacent the rear end of the final set of units andcomprises spaced uprights 65- and 66 connected by cross members 67.Spaced longitudinal strips 68 are silpported at one end upon one .of thecross members'67 with the other end inclined downwardly into one of thetroughs 30 and supported by brackets 69 thereon. The strips 68 serve assupports or platforms upon which the receptacles 38 are moved by theconveyors. A spray device is arranged below each of these fgroupsofstrips and comprises a plurality o perforated pipes 7 0 connected with a'watermain 71 in which is arranged a self-closing valve 7 2 having anoperating lever 7 3 extending into the path of movement of thereceptacles 38.

As 'each receptacle 38 is moved along the strips 68 it engages the lever73 to open the valve 7 2 to cause a spray of water to be directed uponthe bottom of the receptacle and warm the same sufliciently .to loosenfish frozen thereto. When the receptacle has 1 passed the lever 73 thevalve 7 2 automatically closes and stops the spray. In this manner thespray is directed upon the receptacle a predetermined lengthof timesufficien't to loosen the fish but insufiicient to warm the fish to adetrimental extent.

It will be noted that in the. apparatus of the invention the fish arefrozen in a rapld manner inasmuch as the receptacles holding the samearenot only in direct contact with the cool brine but are also at all timesin di-' rect metal-to metal contact with the flanges- 37 of the fins 36,and therefore in a direct heat conducting relation, by an all-metal pathorconnection, with the refrigerant in :the condu1ts 35, thereby removingthe heat below bottom thereof n means S s from the fish in a rapidmanner. urthermore, inasmuch as the level of the brine is above thesurface upon which the receptacles rest, the brine'exerts a buoyantaction upon I claim a trough containing a cooling fluid, a heat exchangeelement in said trough having a heat conducting surface, a heatconducting receptacle movable on and in direct contact with saidsurface, and means for moving said receptacle on said surface. 4 2.In'an' apparatus for freezing fish and s'imilar foodstuffs, a freezingunit comprising a refrigerant'conduit, heat conducting fins spaced aparton' said conduit and having their outer ends located to form asubstantially continuous plane surface, a heat conducting receptacleadapted to be supported on said surface, and means for moving saidreceptacle along said surface.

,3. In an apparatus for freezing fish and similar foodstuffs, thecombination of a frame, a freezing unit supported in said I framecomprising a trough containing a cooling fluid, a heat exchange elementin said trough having a heat conducting surface and submerged in saidfluid, a heat conducting re- I ceptacle movable on said surface, andmeans for moving said receptacle.

4. In an apparatus for freezlng fish and similar foodstuffs, a freezingunit compris ing a trough adapted to contain a cooling liq-' uid, arefrigerant conduit in said trough, heat I conducting fins spaced aparton said conduit and having their outer ends located to form asubstantially continuous plane surface, a heat conducting receptacleadapted to be supported on said surface, and means for moving saidreceptacle alongsaidsurface. 5. In an apparatus for freezing fish andsimilar foodstuffs, the combination of a 7 frame, a freezing unitsupported in said frame. comprising a trough, a refrigerant conduitin'said trough, means within said trough-for supporting fish in directheat conducting relation to said conduit, and means for adjusting theposition of said trough in said frame.

6. In an apparatus of the character described, the combination of aframe, a freezmg unit supported in ra1sed posltion in said framecomprising a trough, a heat exchange element in said trough having aheat conducting surface within said trough connected in heat conductingrelation with said con-' duit, a heat conducting receptacle movable onsaid surface, a conveyor supported by said trough and movable above thetop and conveyor adapted to engage said receptacle to move the samealong said surface. I 7. In an apparatus of the character de scribed,the combination ofa frame, a f'reezing unit supported in raised positionin said frame comprising a' trough, a heat exchange element in saidtrough-having a heat conducting surface, a' heat conducting receptaclemovable on said surface,'a conveyor supportand engage said receptacle tomove the same alongsaid surface. 8. In an apparatus of the characterdescribed, the combination of aframe including spaced screws, a nutsimilarly positioned on each screw, a cross member extending between andsurrounding-said screws and having its opposite ends resting on saidnuts, a trough supported by said cross member, a refrigerant conduit insaid trough, and means for supporting flsh'in direct heat conductingrelation to said conduit.

9. In an apparatus of the character described, the combination of aframe including spaced screws, a plurality of nuts similarly positionedin spaced relation on each of said screws, cross members extendingbetween and surroundlng said screws and havingthelr opposite endsresting on similarly positioned nuts, means for locking a pair of saidnuts I porting nuts to said screws.

supporting one cross member, and means for locking another pair of crossmembers sup- 10. In an apparatus of the character described, thecombination of a frame, a freezing unit supported in said frame, a spraydevice supported within the frame, and means for moving a fishcontaining receptacle in a path through said freezing unit and abovesaid spray device, said spray device being arranged to direct a spray ofrelatively warm fluid upon the bottom of said receptacle.

11. In "an apparatus of the character described, the combinationof aframe, a freezi-ng'unit supported in said frame, a spray devicesupported within the frame, means for moving a fish containingreceptacle in apath throughsaitl freezing unit andabove said spraydevice, said spray device being arranged to direct a spray of relativelywarm fluid upon the bottom of said receptacle, and. means forcontrolling the length of time said spray is directed upon saidreceptacle.

12. In an apparatus of the character described, the combination of aframe, a freezing unit supported in saidframe, a spray device supportedwithin the frame, means for moving a fish containing receptacle in apath throughsaid freezing unit and above said spray device, ,said spraydevice being arranged to direct a spray of relativelywarm fluid upon tle bottom of said receptacle, a self-closing valve for controlling theoperation of said spray, and a control lever connected' tosaid valve andextending into the path of movement of said receptacle.

13. The hereindescribed method of freezing fish and similar foodstuffswhich includes placing the same in a metal receptacle and moving saidreceptacle over and in direct contact with a heat exchange elementcontaining a suitable refrigerant andsubmerged in a cooling liquid. r AJ 14. The hereindescribed method of freezing fish and similar foodstuffswhich includes placing the same in a metal rece tacle and moving saidreceptacle over an in direct contact with a heat exchange elementcontaining a suitable refrigerant and submerged in a coolingliquid, andcirculating said liquid in the opposite direction to the travel of saidreceptacle. g 15. In an apparatus for freezing fishand, similarfoodstufls', the combination of a frame, a freezing unit supported insaid franre comprising a trough containing a' cooling fluid, a heatexchange element in said trough having a heat conducting surfacesubmerged in said fluid, a heat conducting receptacle movable on saidsurface, means for .moving said receptacle, and means forcirculatingsaid fluid'in a direction opposite to the direction of movement of thereceptacle. I

16. In an apparatus for freezing fish and similar foodstuffs, incombination, a trough, a heat exchange element extending longitudinallyof said trough and having a substantially horizontal heat conducting surface, a heat conducting receptacle supported on said surface in directcontact therewith and movable thereover, and a cooling'liquid fillingsaidtrough to a depth sufficient to cover said surface but insuflicientto float said receptacle out of contact therewith.

17. The method of freezing fish and similar foodstufl's which comprisesplacing the fish in a heat conducting receptacle, moving said receptaclewhile in substantially uninterrupted heat conducting contact with arefrigerant conduit, and submerging said conduit in a cooling liquid inamount insufficient to float said receptacle out of contact with theconduit.

'18. The method of freezing fish and similar foodstuffs which comprisesplacing the fish in a heat conducting receptacle, moving said receptaclewhile in substantially uninterrupted heat conducting contact with arefrigerant conduit, and circulating over said conduit and in contactwith said receptacle a cooling liquid in amount insufficient to floatsaid receptacle out of contact with said conduit. i

19. The method of freezing fish and simi lar foodstuffs which comprisesplacing the 120 same in a metal receptacle and moving said receptacleover and in direct metal to metal contact with a'metallic heat exchangeelement containing a suitable refrigerant.

20. In an apparatus for freezing fish and 125 similar foodstuffs, afreezing unit comprising a metallic heat exchange element having ametallic surface, .a metal receptacle adapted to contain fish movable onand in direct contact with said surface, and means for 1 moving saidreceptacle on said surface, whereby direct metal to metal contact ismaintained substantially uninterruptedl between said heat exchangeelement an the fish in said receptacle.

Intestimony whereof I aflix my signature.

ARTHUR C. WALWORTH.

